In recent decades, the face of the American family has changed considerably, along with our understanding of marriage. Consider that over 40% of all U.S. births occurred to unmarried mothers in 2014. The rate was even higher among non-college-educated mothers, at 62%. Given that numerous studies have shown children typically do best in households with two married parents, this poses a two-part question for family policy makers: What is driving this change, and what, if anything, can be done to nurture a reversal?

By looking at various regions across the country where fracking could happen, geologically speaking—whether or not it has been authorized by local authorities—the two tested a hypothesis about whether low marriage rates are related to non-college educated men’s poor economic prospects. With fracking representing a catalyst for economic growth, the study’s authors asked: when a region sees economic growth and rising wages for men (making them “marriageable”), is there a corresponding increase in the birth rate? And do more women wed before bearing those children?

The short answer is yes, and no. In studying young mothers (women ages 18-34), the study’s authors observed an increase in the number of births. For every additional $1,000 “of fracking production per capita,” there is “an increase of 5.96 births per 1,000 women.”

However, rising wages for men seemingly do not change women’s connubial calculus in the 21st century. While areas with economic growth saw a rise in fertility, babies were born to both married and unmarried mothers, and there was no corresponding rise in the rate of marriage. “During our period of analysis,” the authors write, “over 71 percent of these births were to single women, consistent with the general finding that births to young women are births to less-educated women.” Further, areas where non-marital births were already common, saw more of them.

The authors compared these findings to Appalachia’s coal boom in the 1970s and 1980s. That earlier boom sparked an increase in both marriage and marital childbearing, along with a decrease in non-marital childbearing (page 4). In an emailed response to a question I posed, Professor Kearney noted, “We interpret the evidence as showing similar marital birth effects across periods. Those numbers are not statistically different [from] one another.”

However, there is a clear uptick in non-marital births associated with the fracking boom, mirroring recent decades’ uptick in non-marital births. Given that, Kearney’s emailed response about the demographics of the studied population is also worth noting: “In fracking areas, 64.1% of 18-34-year-olds are white non-Hispanic, as compared to 62.7% in non-fracking [regions].” The white working class, which would heavily populate the data from both energy booms, was overwhelmingly traditional in its family patterns 30 or 40 years ago. That is no longer the case.

But what explains the different reactions to similar economic events? The authors note that not only are there now more women in the workforce but that women saw their wages rise this time around, “albeit to a lesser extent than for men.” They also speculate that women might not seek spouses from a pool of men laboring in fracking because “fracking jobs are particularly onerous.” For this writer, the most convincing explanation was the authors’ observation that “Social context partially determines the family formation response to a positive income or earnings shock.”

[F]inally, the thing that really makes economists squirm when we look at these results, if we’re honest with ourselves, is that the factors that seem to be correlated—again, these are the clues as to what we might need to be pushing on—they are really more about culture than are policy levers. And this keeps coming up.

Daniel Patrick Moynihan and other early Neocons would have agreed that culture is powerful. Now, the question for policymakers interested in strengthening fragile families is what to do about it.

Melissa Langsam Braunstein, a former U.S. Department of State speechwriter, is now an independent writer in Washington, D.C. She frequently writes about culture, religion, and issues affecting families. She shares all of her writing on her website.